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From: Dono. on 21 Oct 2009 11:20
On Oct 21, 7:20 am, tominlag...(a)yahoo.com wrote:
>
> >Read the Mathpages analysis, instead of just looking at the pictures :):)
>
> I read it. How otherwise could I have discovered it contained a lie
> about the emission theory?

So, you persist in your idiotic assertion that Sagnac does not
disprove the emission theory of Ritz, right?
I thought you were a crackpot the forst time you posted, now that you
are confirming it.....there is absolutely no doubt.
From: Dono. on 21 Oct 2009 11:25
On Oct 21, 8:06 am, tominlag...(a)yahoo.com wrote:
> When you look at the Mathpages
> description, you will note that he uses c+v and c-v in his
> calculation. Are those real speeds or apparent speeds?

They are CLOSING SPEEDS, idiot.

In the clockwise direction the light chases the mirrors

c*t_CW=2piR+v*t_CW

In the counterclockwise direction, the light front encounters the
mirrors:

c*T_CCW+v*t_CCW=2pi*R

Therefore:

t_CW=2pi*R/(c-v)
t_CCW=2pi*R/(c+v)

Do you understand now?
What other lie or error did you find on the mathpage?
From: tominlaguna on 21 Oct 2009 12:09
On Tue, 20 Oct 2009 00:25:01 -0500, Tom Roberts
<tjroberts137(a)sbcglobal.net> wrote:

>tominlaguna(a)yahoo.com wrote:
>> But for the moment I would like to focus on the issue of Snell's law
>> and how it plays into your thesis. When I think of Snell's law, I am
>> thinking of refraction not reflection, unless it is total internal
>> reflection. Nonetheless, I am not aware of any way to differentiate
>> between SRT and Ballistic theory when there is no relative motion
>> between the source and mirrors or refracting medium.
>
>Snell's law also applies to mirrors -- when measured from the normal to
>the mirror, the incoming and outgoing angles are equal ("angle of
>incidence equals angle of reflection"). For a ballistic theory, if
>Snell's law holds in the rest frame of the mirror such that the light
>rays' speeds are equal in that frame, then it predicts a null result for
>a Sagnac interferometer in vacuum using mirrors [#] -- that is
>inconsistent with actual measurements, and all such theories are
>refuted. For a ballistic theory in which Snell's law does not hold in
>the rest frame of the mirror, then it is refuted by other measurements.
>
> [#] This is a nontrivial calculation, as a different
> inertial frame must be used for each mirror. One must
> also assume Galilean relativity to transform to the lab
> frame.
>
>
>Tom Roberts

Actually, I like to think of a generalized concept called Snell's Law.
For me, it reads something like this:

Snell's law gives the relationship between angles of incidence and
refraction or reflection for a wave impinging on an interface such
that the speed of the incoming wave times the SIN of the angle it
makes with the normal to that surface equals the speed of the
reflected or refracted wave times the SIN of the angle it makes with
the normal to that surface.

You would have trouble with it because it opens the door for a
reflected wave to have a speed other than c. I believe that is why
you rarely see the term Snell's Law of Reflection. The common term is
The Law of Reflection.

I think there is another problem trying to use Snell's Law of
Reflection with SRT and that has to do with moving mirrors. In
Ditchburn's book "Light" (1976) page 418, he shows the angle of
incidence and the angle of reflection to be different for a moving
mirror, though the speed of the incoming and reflected waves are
identical. He does not (cannot) make reference to Snell.

In Waldron's book, "The Wave and Ballistic Theories of Light" (1977)
page 162, he shows the generalized Snell's law which occurs when there
is relative motion between the source and the mirror. It is ONLY when
there is RELATIVE motion between source and mirror that a change in
the speed of light can occur with the emission theory.

Since there is no relative motion between the Sagnac source and the
Sagnac mirrors, there is no change in light speed. It is plain and
simple classical physics as described by Dufour and Prunier.
From: Dono. on 21 Oct 2009 12:39
On Oct 21, 9:09 am, tominlag...(a)yahoo.com wrote:
>
>
> I think there is another problem trying to use Snell's Law of
> Reflection with SRT and that has to do with moving mirrors. In
> Ditchburn's book "Light" (1976) page 418, he shows the angle of
> incidence and the angle of reflection to be different for a moving
> mirror, though the speed of the incoming and reflected waves are
> identical. He does not (cannot) make reference to Snell.
>

You don't understand what you are reading. The above is true ONLY IF
the mirror is imperfect, i.e. f_incident <> f_reflected. For perfect
mirrors the Snell Law (alpha_incident=alpha_reflected) holds. See W.
Pauli, "The Theory of Relativity", page 94.

From: Tom Roberts on 21 Oct 2009 12:49
tominlaguna(a)yahoo.com wrote:
> I think there is another problem trying to use Snell's Law of
> Reflection with SRT and that has to do with moving mirrors. In
> Ditchburn's book "Light" (1976) page 418, he shows the angle of
> incidence and the angle of reflection to be different for a moving
> mirror, though the speed of the incoming and reflected waves are
> identical.

This is not a problem: Snell's law for mirrors applies ONLY in the inertial
frame of the mirror. When viewed using other frames, the angle of reflection can
be different from the angle of incidence. This is just basic SR applied to the
physical situation, and there's no contradiction or problem here.


> In Waldron's book, "The Wave and Ballistic Theories of Light" (1977)
> page 162, he shows the generalized Snell's law which occurs when there
> is relative motion between the source and the mirror. It is ONLY when
> there is RELATIVE motion between source and mirror that a change in
> the speed of light can occur with the emission theory.
>
> Since there is no relative motion between the Sagnac source and the
> Sagnac mirrors, there is no change in light speed. It is plain and
> simple classical physics as described by Dufour and Prunier.

I don't have those references, but statements like "there is no relative motion
between the Sagnac source and the Sagnac mirrors" are FAR TOO AMBIGUOUS -- you
MUST state in which frame or coordinates this claim is valid. In particular, in
the inertial frame of the center it is just plain wrong. But in the rotating
system it is correct.

Consider Sagnac interferometer in vacuum using mirrors:
In such an emission theory, analyzed in the rotating coordinates, the speed of
light is c for both rays, and the path lengths are equal, so the prediction is
no fringe shift. In such an emission theory, analyzed in the inertial frame of
the center, the speed of light varies for each leg, and the two rays have
different path lengths; a careful computation putting it all together gives the
same prediction of no fringe shift [reference lost].

Bottom line: such an emission theory is refuted by Sagnac's observations, as I said.


Tom Roberts
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